The HTM4S is a "better" speaker. If you plan on upgrading any time soon to 80xS type Fronts, then I would get the HTM4S.
The HTM2 is the match for your N802 speakers. If you plan on keeping the N802 speakers for a while, then that is the one you want.
Those are perfect world recommendations. I started with the HMT1 in front, which is the same match as the HTM2. Later I added 804S and 803S speakers. Now I have a mismatch up front. You can hear a slight mismatch, but it isn't bad. It is still a sweet sounding setup.
To correct it, I would have to spend ~$800 to upgrade it. So far I have found other parts of my audio system that need more attention/fixing than this mismatch so I am fixing them first.
If you don't have a Center or plan to upgrade to 80xS speakers anytime soon, I would go ahead with the HTM4S. If you already have the HTM2, I would keep it and address other parts of your system 1st.